Date: Thu, 16 Jan 1997 12:18:14 -0600
Message-Id: <v01530514af051f057317@[128.252.197.88]>
To: abrfhyp@cco.caltech.edu
From: rskubish@pharmdec.wustl.edu (Richard Skubish)
Subject: peptide synthesis -18 mass
>Date: Fri, 23 Aug 1996 15:34:42 -0700
>X-Sender: schooley@med.unr.edu
>Mime-Version: 1.0
>Old-To: RIFLEMAN@uthscsa.edu, abrf@aecom.yu.edu
>From: schooley@unr.edu (David A. Schooley)
>Subject: Re: peptide synthesis -18 mass
>To: Recipients of ABRF List <abrf@aecom.yu.edu>
>Sender: Association of Biomolecular Resource Facilities
><abrf-request@aecom.yu.edu>
>Precedence: bulk
>
>Peggy wrote-
>>Is it possible for tyrosine to go to dehydrophenylalanine? NO WAY! That
>>would be a benzyne derivative; decomposes instantly.
>>
>>The -l0 peak seems to be pretty stable.
>Maybe you ought to clarify if you mean -18 here?
>
> Seems to me you almost certainly have an aspartimide here- very
>common. Way to tell is convert to methyl ester(s) and do MS. That allows
>you to count # of carboxyl groups from number of multiples of 14 amu added.
>
>David
>
>David A. Schooley
>Dept. of Biochemistry/330
>Univ. of Nevada
>Reno, NV 89557
>schooley@med.unr.edu
>tel: (702) 784-4136; fax (702) 784-1419
>
Richard Skubish
rskubish@pharmdec.wustl.edu
314-362-0283
Washington University Medical School
Box 8103 - PNACL
660 S. Euclid
St. Louis, MO 63110